The present invention relates to an electrophotography, and more particularly to an electrophotographic apparatus which can form or print any desired number of duplicated copies for each of a plurality of documents or manuscripts in a speedy and simple manner.
In one type of such an electrophotographic apparatus any number of duplicated copies can be printed by successively repeating development and transferring steps for the same and single latent image which has been once formed on the photosensitive member by a single exposure-scanning of the document.
In another type of apparatus a primary electrostatic charge latent image is once formed on a photosensitive screen and any desired number of copies can be formed by successively repeating a step for forming a secondary electrostatic charge latent image on a record paper by means of a corona ion stream which is modulated by the primary electrostatic charge latent image on the screen, and a step for developing the secondary image with toner particles to form a visible toner image.
The electrophotographic apparatus of the kind mentioned above has an advantage that during the multiple duplication of a document a next document can be set in the apparatus. If it is required to form the same number of copies for successive documents, this copy number can be set in a copy number setting member such as a copy number dial, but is is intended to print different copies for successive documents, the copy number has to be changed. In general multiple copies are formed by multiple exposure-scanning for the single document and thus the document could not be exchanged by a next document. That is after the given number of copies have been printed the next document is set in the apparatus. Therefore a desired copy number to be obtained by the new document can be set by the copy number dial when the new document is set in the apparatus. However in the above mentioned multiple copying machine forming a plurality of copies from the single electrostatic charge latent image it is possible to set a next document while the desired number of copies for the present document are printed, and thus it is quite inconvenient to set a desired number of copies to be formed for the next document after the copies for the present document have been obtained.